Validating and valuating paper currency bills

ABSTRACT

In one embodiment, a method includes obtaining a first plurality of identifiers associated with a first plurality of paper currency bills, wherein the first plurality of identifiers are obtained from the first plurality of paper currency bills at least in part by wireless communication with the first plurality of paper currency bills; determining whether each of the first plurality of identifiers associated with the first plurality of paper currency bills is valid, including comparing each of the first plurality of identifiers associated with the first plurality of paper currency bills to a first set of valid identifiers; and determining a value of the first plurality of paper currency bills, utilizing the first plurality of identifiers.

FIELD OF THE INVENTION

The present invention relates to systems and methods relating to itemshaving wireless devices coupled thereto or embedded therein.

BACKGROUND

Radio Frequency Identification (RFID) technology employs a radiofrequency (“RF”) wireless link and ultra-small embedded computercircuitry. RFID technology allows physical objects to be identified andtracked via these wireless “tags”. It functions like a bar code thatcommunicates to the reader automatically without requiring manualline-of-sight scanning or singulation of the objects. RFID promises toradically transform the retail, pharmaceutical, military, andtransportation industries.

Several advantages of RFID technology are summarized in Table 1:

TABLE 1 Identification without visual contact Able to read/write Able tostore information in tag Information can be renewed anytime Unique itemidentification Can withstand harsh environment Reusable HighFlexibility/Value

As shown in FIG. 1, a basic RFID system 100 includes a tag 102, a reader104, and an optional server 106. The tag 102 includes an integratedcircuit (IC) chip and an antenna. The IC chip includes a digital decoderneeded to execute the computer commands the tag 102 receives from thetag reader 104. The IC chip also includes a power supply circuit toextract and regulate power from the RF reader; a detector to decodesignals from the reader; a back-scattering modulator to send data backto the reader; anti-collision protocol circuits; and at least enoughEEPROM memory to store its EPC code.

Communication begins with a reader 104 sending out signals to find thetag 102. When the radio wave hits the tag 102 and the tag 102 recognizesthe reader's signal, the reader 104 decodes the data programmed into thetag 102. The information can then be passed to a server 106 forprocessing, storage, and/or propagation to another computing device. Bytagging a variety of items, information about the nature and location ofgoods can be known instantly and automatically.

The system uses reflected or “backscattered” radio frequency (RF) wavesto transmit information from the tag 102 to the reader 104. Sincepassive (Class-1 and Class-2) tags get all of their power from thereader signal, the tags are only powered when in the beam of the reader104.

The Auto ID Center EPC-Compliant tag classes are set forth below:

Class-1

-   -   Identity tags (RF user programmable, maximum range ˜3 m)

Class-2

-   -   Memory tags (8 bits to 128 Mbits programmable at maximum ˜3 m        range)    -   Security & privacy protection

Class-3

-   -   Battery tags (256 bits to 64 Kb)    -   Self-Powered Backscatter (internal clock, sensor interface        support)    -   ˜100 meter range

Class-4

-   -   Active tags    -   Active transmission (permits tag-speaks-first operating modes)    -   Up to 30,000 meter range

In RFID systems where passive receivers (i.e., Class-1 tags) are able tocapture enough energy from the transmitted RF to power the device, nobatteries are necessary. In systems where distance prevents powering adevice in this manner, an alternative power source must be used. Forthese “alternate” systems (also known as active or semi-passive),batteries are the most common form of power. This greatly increases readrange, and the reliability of tag reads, because the tag doesn't needpower from the reader. Class-3 tags only need a 10 mV signal from thereader in comparison to the 500 mV that a Class-1 tag needs to operate.This 2,500:1 reduction in power requirement permits Class-3 tags tooperate out to a distance of 100 meters or more compared with a Class-1range of only about 3 meters.

Conventional RFID tags interact strongly with the electrical andmagnetic fields near them; in fact most are resonant with Q-factorsranging between 5 and 100. Unfortunately, this also means that thesetags also interact very strongly with each other in ways that oftenprevents the tags from being read at all. The problem becomes even worsewhen the tagged objects are thin and flat—like gaming chips, currency,documents, etc. In such a stack, the energy received by each object/tagis highly non-uniform, with the outermost objects receiving most of theenergy and the interior objects shielded by the outer objects andreceiving virtually no energy at all. In other words, the antenna of theouter tag serves as a Faraday shield to anything behind it. The tags onthe outside of the stack will continue to work well, but the tags on theinside of the stack work very poorly if at all. For these reasonsconventional wisdom was that it impossible to read a stack of taggeditems.

As touched on above, in addition to blocking RF energy, the antennaeinterfere with RF energy in their vicinities, potentially rendering theRF signal unreadable to tags nearby. This phenomenon is best understoodby considering the radar profile of the antenna. The radar profile ofthe antenna may often be larger than the actual physical profile of theantenna, and can be a large as 100× the physical profile of the antenna.Accordingly, the problems mentioned above can also be found inassemblies of tagged objects that are not necessarily stacked.

There are many instances where tags could be stacked or assembled inclose proximity. One implementation is in gaming chips. Another is paperobjects such as birth certificates, paper currency, etc. Significanttag-to-tag interactions and variability also occur even with a row oftagged objects sitting on a shelf. It would be desirable to read a stackof gaming chips, stack of tagged currency, file of papers, etc. in onepass via RFID technology.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and advantages of the presentinvention, as well as the preferred mode of use, reference should bemade to the following detailed description read in conjunction with theaccompanying drawings.

FIG. 1 is a system diagram of an RFID system.

FIG. 2 is a high level circuit diagram showing a circuit forimplementation in a RF device according to one embodiment.

FIG. 3 is a high level circuit diagram of a monolithic semiconductorintegrated circuit that may form part of the circuit of FIG. 2.

FIG. 4 illustrates a system according to one embodiment.

FIG. 5 is a partial cross sectional view taken along Line 5-5 of FIG. 4.

FIG. 6 is a partial cross sectional view of a system according to oneembodiment.

FIG. 7 is a partial cross sectional view of a system according to oneembodiment.

FIG. 8 is a partial cross sectional view taken along Line 8-8 of FIG. 4.

FIG. 9 illustrates a network architecture, in accordance with oneembodiment.

FIG. 10 shows a representative hardware environment that may beassociated with the servers and/or clients of FIG. 9, in accordance withone embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

The following description is made for the purpose of illustrating thegeneral principles of the present invention and is not meant to limitthe inventive concepts claimed herein. Further, particular featuresdescribed herein can be used in combination with other describedfeatures in each of the various possible combinations and permutations.

Unless otherwise specifically defined herein, all terms are to be giventheir broadest possible interpretation including meanings implied fromthe specification as well as meanings understood by those skilled in theart and/or as defined in dictionaries, treatises, etc.

It must also be noted that, as used in the specification and theappended claims, the singular forms “a,” “an” and “the” include pluralreferents unless otherwise specified. A method according to one generalembodiment includes obtaining an identifier from a gaming chip, whereinthe identifier is obtained from the gaming chip at least in part bywireless communication with the gaming chip; determining whether theidentifier is invalid; and outputting an indication that the identifieris invalid. A system for performing the method may include a processorand/or other hardware and/or logic for performing one or more of theoperations of the method. The processor may be hardware associated witha reader, and/or may be part of a system in communication with thereader such as a backend system, server, network-accessible site ordevice, etc.

A method according to another general embodiment includes obtaining anidentifier from a gaming chip, wherein the identifier is obtained fromthe gaming chip at least in part by wireless communication with thegaming chip; determining a source of the gaming chip based on theidentifier; and outputting an indication of the source to at least oneof a user, a computer, and an application. A system for performing themethod may include a processor and/or other hardware and/or logic forperforming one or more of the operations of the method. The processormay be hardware associated with a reader, and/or may be part of a systemin communication with the reader such as a backend system, server,network-accessible site or device, etc.

A method according to another general embodiment includes determining avalue of a gaming chip or chips at a table or player position; detectinga change in value of the gaming chip or chips at the table or playerposition; and determining whether the change in value is valid. A systemfor performing the method may include a processor and/or other hardwareand/or logic for performing one or more of the operations of the method.The processor may be hardware associated with a reader, and/or may bepart of a system in communication with the reader such as a backendsystem, server, network-accessible site or device, etc.

A method according to another general embodiment includes determining avalue of a gaming chip or chips at a player position using a radiofrequency signal; recording in a database the value of the gaming chipor chips at the player position in association with identity informationof the player. A system for performing the method may include aprocessor and/or other hardware and/or logic for performing one or moreof the operations of the method. The processor may be hardwareassociated with a reader, and/or may be part of a system incommunication with the reader such as a backend system, server,network-accessible site or device, etc.

A method according to another general embodiment includes determiningvalues of gaming chips played at a player position on a gaming tableduring games; recording in a database the values of the gaming chipsplayed at the player position in association with identity informationof the player. A system for performing the method may include aprocessor and/or other hardware and/or logic for performing one or moreof the operations of the method. The processor may be hardwareassociated with a reader, and/or may be part of a system incommunication with the reader such as a backend system, server,network-accessible site or device, etc.

A system according to another general embodiment includes a gaming tablehaving a plurality of player positions; and a radio frequency (RF)antenna near each player position for wirelessly communicating with atleast one of gaming chips and an item preassociated with a particularplayer at each player position of a gaming table. Gaming chips may alsobe part of the system.

Some embodiments of the present invention may use a Radio Frequency (RF)device with a circuit and a “semitransparent” antenna of a typedisclosed in U.S. Patent Pub. No. 2006/0250251 A1, published Nov. 9,2006, which is herein incorporated by reference. The semitransparentantenna gathers some of the RF energy, but most of the energy in the RFwave does not couple into the antenna. Accordingly, because the antennain some such embodiments minimally affects the electromagnetic RF fieldssurrounding the antenna even in the vicinity of the antenna, assembliesof objects carrying the RF devices can be formed while maintainingacceptable communications with the RF devices.

Other embodiments may use conventional antenna designs of a type knownin the art.

Many types of devices can take advantage of the embodiments disclosedherein, including but not limited to Radio Frequency Identification(RFID) systems and other wireless devices/systems; pacemakers; portableelectronic devices; remote controllers for televisions, audio devices,and other electronic devices; smoke detectors; etc. To provide acontext, and to aid in understanding the various embodiments of theinvention, much of the present description shall be presented in termsof an RFID system such as that shown in FIG. 1. It should be kept inmind that this is done by way of example only, and the invention is notto be limited to RFID systems, as one skilled in the art will appreciatehow to implement the teachings herein into electronics devices inhardware and/or software, either or both of which may be generallyreferred to as “logic.” Examples of hardware include ApplicationSpecific Integrated Circuits (ASICs), printed circuits, monolithiccircuits, reconfigurable hardware such as Field Programmable Gate Arrays(FPGAs), etc. Further, the methodology disclosed herein can also beincorporated into a computer program product, such as a computer disccontaining software. Further, such software can be downloadable orotherwise transferable from one computing device to another via network,nonvolatile memory device, etc.

FIG. 2 illustrates a Radio Frequency (RF) device 200, e.g., RFID tagaccording to one embodiment. The radio frequency data communicationdevice 200 includes an integrated circuit 204, a power source 206connected to the integrated circuit 204 to supply power to theintegrated circuit 204, and at least one antenna 202 connected to theintegrated circuit 204 for radio frequency transmission and reception bythe integrated circuit 204. For purposes of this disclosure, includingthe appended claims, the term “integrated circuit” and “circuit” shallbe defined as a combination of interconnected circuit elementsassociated on or within a continuous substrate. For purposes of thisdisclosure, including the appended claims, the term “semiconductivesubstrate” is defined to mean any construction comprising semiconductivematerial, including, but not limited to, bulk semiconductive materialssuch as a semiconductive wafer (either alone or in assemblies comprisingother materials thereon), and semiconductive material layers (eitheralone or in assemblies comprising other materials). For purposes of thisdisclosure, including the appended claims, the term “substrate” refersto any supporting structure, including, but not limited to, thesemiconductive substrates described above, printed circuit boards(PCBs), adhesive backings, etc. In the embodiment illustrated in FIG. 2,the integrated circuit 204 is a monolithic integrated circuit. Forpurposes of this disclosure, including the appended claims, the term“monolithic integrated circuit” shall be defined as an integratedcircuit wherein all circuit components are manufactured into or on topof a single chip of silicon or layer of semiconductive material. Theintegrated circuit 204 will be described in greater detail below. Thepower source 206 is a battery and/or a power supply circuit thatextracts and regulates power from the RF reader signal.

The radio frequency data communication device 200 can be included in anyappropriate housing or packaging, made of plastic or any other suitablematerial. The device 200 is of a small size that lends itself toapplications employing small housings, such as cards, miniature tags,etc. Larger housings can also be employed. The device 200, housed in anyappropriate housing, can be supported from or attached to an object inany desired manner; for example using double sided tape, glue, lanyards,leash, nails, staples, rivets, or any other fastener. The housing can besewn on to an object, hung from an object, implanted in an object(hidden), etc. A description of illustrative RFID tags, systems, andmethods of user are disclosed in U.S. Patent Appl. Pub. No.2004/0201457A1 to O'Toole et al., which is herein incorporated byreference.

Various configurations are possible for the antenna 202. The integratedcircuit 204 includes a receiver 300 and a transmitter 302 (FIG. 3). Inone embodiment, separate antennas 314 and 316 are provided for receiverand transmitter of the integrated circuit 204. In another embodiment(FIG. 2), a single antenna is shared by the receiver and transmittersections. In one embodiment, the antenna is defined by conductive paste(e.g., epoxy) screened onto a card or housing. In another embodiment,the antenna is formed of a conducting polymer. An advantage ofconducting polymers is that the sheet resistivity is controllable in arange from 1 Ω/sq to 1,000,000 Ω/sq. In the illustrated embodiment, theantenna is a planar conductive material such as Indium Tin Oxide orother suitable high sheet resistance metal-based material conductivelybonded to the integrated circuit via bonding pads.

In an embodiment where a single antenna is employed, that single antennacan be a folded dipole antenna defining a continuous conductive path, orloop, of microstrip. Alternatively, the antenna can be constructed as acontinuous loop antenna. Additional antenna designs are disclosed incopending U.S. patent application Ser. No. 11/073,239 filed on Mar. 4,2005 with title “COMPACT OMNI-DIRECTIONAL RF SYSTEM,” and which isherein incorporated by reference.

In some embodiments described herein, the tag antennas are designed tocontrol and limit their interactions with the RF fields such that mostof the RF wave striking or in the immediate vicinity of the antenna doesnot couple into the antenna. Thus, the antenna minimally affects theelectromagnetic RF fields surrounding the antenna even in the vicinityof the antenna. By “minimally affects” what is meant is that at leastabout 50%, and preferably greater than about 90%, of the RF energystriking the antenna and in the vicinity of the antenna is useable byanother RF device in the vicinity of the tag.

In this antenna design, the inductive impedance elements are reduced andthe antenna impedance increased to the point where the residualinductance of the tag antenna has only minimal effect on the antenna'simpedance. Such antennas are preferably constructed of a planarconductor having a sheet resistivity of greater than about 1 Ω/sq,preferably greater than about 10 Ω/sq. To prevent excessive loading ofthis high impedance antenna, the tag circuit input impedance ispreferably as high as possible. A total impedance of the RF devicepresented to the RF wave is preferably greater than about 1000Ω. Oneembodiment has a resistive impedance of >100 KΩ, and an input bypasscapacitance of less than 0.02 pf corresponding to a reactive bypassimpedance of at least about 10 KΩ. At 900 MHz, a non-resonant antennadesign may include fabricating the antenna using conductors with a sheetresistivity of, for instance about 1000 Ω/sq, and designing the tag tohave a total tag impedance of perhaps 100 KΩ.

The impedance of the semi-transparent tags may be adjusted to theobjects to which they are attached so that even a tightly packedassembly of such objects will appear to the RF propagating signal as amoderately lossey RF propagation medium. For instance, tags on stackableboxes 10 mm thick could be equipped with 10 KΩ antennas; tags on 1 mmthick gaming chips could have 100 KΩ antennas; tags on 0.2 mm thickcurrency could have 500 KΩ antennas, etc. The total admittance ordissipation-factor of the tag/package system is preferably kept roughlyconstant per volume so that RF radiation can pass through the assemblywithout excessive attenuation or reflection.

While the individual performance of these semi-transparent tags will besignificantly inferior to the individual performance of conventionaltags, the performance of these semi-transparent tags will not bedegraded as much by the presence of other near-by semi-transparent tags.For example, while a conventional tagged gaming chip might have a 100 mrange in free space, the range of that same tagged gaming chip would bereduced to less than 0.01 m when sandwiched between a dozen of othersimilar gaming chips.

On the other hand, a gaming chip with a semi-transparent design mighthave a free space range of only 10 m, but continue to work at up to 3 meven when totally surrounded by other gaming chips tagged withsemi-transparent devices.

This technique therefore provides a way to tag objects and read themeven under adverse conditions that has heretofore been consideredimpossible. This includes directly reading a stack of currency or otherpaper documents, reading tags on the inside of a stack of gaming chips,etc. Preferably, for a plurality of RFID tagged objects, an operatingrange of the objects varies by less than 50% even when the objects arepositioned directly adjacent (e.g., on top of or beside) one another.

With continued reference to FIG. 2, if the power source 206 may be abattery. The battery can take any suitable form. Preferably, the batterytype will be selected depending on weight, size, and life requirementsfor a particular application. Preferably, the battery is formed by thickfilm deposition of high-sheet-resistivity materials so that the batteryitself is also semi-transparent to the RF carrier signal. Alternatively,a metallic button-type cell could be used as long as the battery size iskept small compared to the wavelength of the RF carrier. Instead ofusing a battery, other suitable power sources can be employed such as RFenergy harvesting circuitry as described below and/or of a type known inthe art.

FIG. 3 is a high level circuit schematic of the integrated circuit 204utilized in the device of FIG. 2. In the embodiment shown in FIG. 3, theintegrated circuit 204 is a monolithic integrated circuit. Moreparticularly, in the illustrated embodiment, the integrated circuit 204includes the receiver 300, the transmitter 302, a micro controller ormicroprocessor 304, a wake up timer and logic circuit 306, a clockrecovery and data recovery circuit 308, and a bias voltage and currentgenerator 312.

In one embodiment, a spread spectrum processing circuit 310 is alsoincluded in the integrated circuit 204 and formed relative to the singledie. In this embodiment, signals received by the receiver 300 aremodulated spread spectrum signals. In an illustrated embodiment, themodulation scheme for replies sent by the transmitter 302 can beselectable. One of the available selections for replies sent by thetransmitter 302 is modulated spread spectrum.

In a method of use, an RFID reader sends an interrogation signal to oneor more RFID tags in range of the reader. One skilled in the art willappreciate that any suitable communication protocol, including securityfeatures, can be used. A tag receiving the signal responds with a tagID. The reader can then use that tag ID to address that particular tag,causing the tag to transmit its stored data. The stored data can be anyvariety of information, and is normally associated with the article towhich the tag is attached. The reader can then tell the tag to turn-offfor now so that it will not continue to respond to the interrogationsignal. The reader will then select another tag ID and poll that tag forits data, and so on until all of the tags have been read. Anysingulation technique known in the art may be used.

A gaming chip according to one embodiment includes a body, preferably ofconventional shape appropriate for the game(s) with which the gamingchip is generally played, and preferably formed at least in part of anRF transmissive (including RF transparent) material such as resin,ceramic, plastic, etc. The gaming chip may also include a circuit; andan antenna coupled to the circuit, where at least 50% of the RF energystriking the antenna passes through the antenna.

In another embodiment, a gaming chip includes a circuit on or within asubstrate; and an antenna coupled to the circuit, wherein the antennaminimally affects electromagnetic RF fields surrounding the antenna evenin the vicinity of the antenna.

In further embodiments, peripheral antennas may be used. Such antennasmay extend along the round outer periphery of the gaming chip for atleast a portion of the length of the antenna. In yet other embodiments,the antenna and/or circuitry may be positioned off-center and/orconfigured so that the antennas of the gaming chips are misaligned whenthe gaming chips are in a stack. An example of such an embodiment mayhave a bow-tie shaped antenna, where the typical randomness of stackingwould tend to result in the wings of the bow-tie shaped antenna beingmisaligned in the axial direction of the stack.

A method for reading a gaming chip according to one embodiment includesobtaining an identifier from a gaming chip e.g., by causing a readerand/or an antenna to send a wireless interrogation signal and receive aresponse from a gaming chip in response to the interrogation signal, byreading a memory storing the identifier previously received from thegaming chip, by requesting the identifier from another system that canor has communicated with the gaming chip, etc.; where the responseincludes an identifier, wherein the identifier is obtained from thegaming chip at least in part by wireless communication with the gamingchip somewhere in the communication chain; determining whether theidentifier is invalid according to some predefined criterion; andoutputting an indication that the identifier is invalid if theidentifier is determined to be invalid and/or outputting an indicationthat the identifier is valid. Of course, as is well known in thegambling industry, gaming chips may be known as poker chips, playingpieces, etc. Generally, gaming chips are associated with a monetaryvalue or a point value, which may in turn be converted to a monetaryvalue or its equivalent.

A system for performing the method may include a processor and/or otherhardware, optionally in combination with additional logic, forperforming one or more of the operations of the method. The processormay be hardware associated with a reader, and/or may be part of a systemin communication with the reader such as a backend system, server,network-accessible site or device, etc.

In one approach, the identifier is unique to the gaming chip. Forexample, the identifier may include a unique serial number or otheridentifier of the gaming chip or circuit.

In another approach, the identifier or portion thereof is unique to acasino (including an entity that owns the casino or family of casinos).For example, the gaming chips associated with a particular casino mayhave a casino-specific identifier, which may be the sole identifier or aportion of a larger identifier. Identifiers in various embodiments mayinclude codes, serial numbers, etc.

In one embodiment, the determination of whether the identifier is validmay include comparing the received identifier to a set of valididentifiers. The set of valid identifiers may be in a table, database,etc. and may correspond to gaming chip identifiers (includingidentifiers assigned to the gaming chip and/or circuit (RFID tag)therein) that, e.g., the casino has authorized for use therein, areknown to be valid, were received from a manufacturer, etc. The set maybe available locally; accessible via network connection e.g., to aremote server; online from a remote site; etc. Moreover, the set mayinclude monetary values and other information associated with the gamingchips, such as source and/or owner/provider of the chip; informationuseful for statistical purposes including last date chip was read, wherechip was played, where the chip has traveled to (e.g., within a casino,to which other casinos, etc.), who purchased or won the chip, etc.; etc.

In another embodiment, determining whether the identifier is invalidincludes comparing the received identifier to identifiers of othergaming chips present in a physical location such as a casino, set ofcasinos, Las Vegas, etc. In one approach, some or all of the readablegaming chips in the casino are polled and their identifiers are stored,at least temporarily, for use in the comparison. If two gaming chipshave the same identifier, then it is likely that one of them iscounterfeit and an indication that one or both of the chips is invalidmay be output. Moreover, the general locations of the gaming chipshaving the matching identifiers may be determined and output.

In yet another embodiment, determining whether the identifier is invalidincludes deciding that the identifier cannot be determined to be valid.For example, the determining step may actually be a validating step,where inability to validate the identifier results in a determinationthat the identifier is invalid. Thus, an alternate embodiment may outputan indication that the identifier is valid depending on the result of avalidating step, regardless of whether an indication of invalidity isoutput.

As an option, an alert may be output if it is determined that theidentifier is invalid. The alert may be visible, audible, electronic,etc. For example, the alert may include a textual message to anoperator; a location on a graphical map of a location or layout of abuilding; an identification of a doorway or area in the vicinity of theinvalid chip; a video or picture of the vicinity of the invalid chip (toperhaps see the person carrying the chip); a light on a gaming table; areadout on a podium screen in the pit of a gaming area; etc.

In one embodiment, a general vicinity of the gaming chip may bedetermined. This may be determined, e.g., by identifying the antenna orreader that is in closest proximity to the chip, triangulationtechniques known in the art, etc.

Preferably, the method is successfully performed for each of a pluralityof gaming chips while the gaming chips are stacked. For example, allgaming chips in a stack may be read while in the stack. Gaming chips areusually maintained and/or transported by players, staff, etc. in stacks.The unique designs of some embodiments of the gaming chips disclosedherein allow reading of a stack of gaming chips.

In one approach, the method is performed individually for each of aplurality of gaming chips at a player location of a table. In anotherapproach, the method is performed when the gaming chip is near adoorway. For example, a stationary antenna may be positioned near thedoorway to read gaming chips passing therethrough. In yet anotherapproach, the method is performed when the gaming chip is near a cagearea. The “cage” is a term known in the art to refer to a location whereplayers may convert gaming chips in to currency or credit, and viceversa.

While various embodiment disclosed herein are compatible with fixedantenna positions, the same and other embodiments may advantageously beused with a handheld reader, where the wireless interrogation signal issent from an antenna of a handheld reader. Moreover, the handheld readermay perform some or all operations of the method. In one embodiment, ahandheld reader can be used to find a particular gaming chip, whethervalid or invalid, using known techniques such as proximity detectiontechniques, etc. In one approach, the poker chip may be read over andover again, and its general location determined based on a strength ofthe response, it being presumed that the response from the gaming chipwill be stronger as the handheld reader antenna becomes closer to thegaming chip.

In one embodiment, a value of the gaming chip may be determined. Inanother embodiment, the identifier is changeable. For example, theidentifier may be stored in a memory or logic of the gaming chip, andselectively updated or overwritten.

A method for reading a gaming chip according to one embodiment includesobtaining an identifier from a gaming chip e.g., by causing a readerand/or an antenna to send a wireless interrogation signal and receive aresponse from a gaming chip in response to the interrogation signal, byreading a memory storing the identifier previously received from thegaming chip, by requesting the identifier from another system that canor has communicated with the gaming chip, etc.; where the responseincludes an identifier, wherein the identifier is obtained from thegaming chip at least in part by wireless communication with the gamingchip; determining a source of the gaming chip based on the identifier;and outputting an indication of the source to at least one of a user, acomputer, and an application. The indication may be an identification ofthe source, some identifier associated with the identity of the source,etc.

A system for performing the method may include a processor and/or otherhardware, optionally in combination with additional logic, forperforming one or more of the operations of the method. The processormay be hardware associated with a reader, and/or may be part of a systemin communication with the reader such as a backend system, server,network-accessible site or device, etc.

The source of the gaming chip may be a casino, entity, etc. The sourceof the gaming chip may also refer to a player that obtained the gamingchip, e.g., at a table, the cage, etc.

In one approach, at least a portion of the identifier identifies thecasino, wherein another portion of the identifier is unique to thegaming chip. In other approaches, the identifier may correspond only tothe source, and a second identifier may be unique to the gaming chip. Inanother approach, the identifier includes a portion that identifies thesource and another portion that is unique to the gaming chip.

In one embodiment, determining a source of the gaming chip includescomparing the received identifier or portion thereof to a set of datacorresponding to potential sources of the gaming chip. The set may be ina table, database, etc. that may include codes that correspond tosources such as casinos, vendors, players or manufacturers; may bereceived from a manufacturer; etc.

A value of the gaming chip may also be determined, e.g., by comparingthe identifier to a set of data, by recognizing a portion of theidentifier preassociated with a value, etc.

Preferably, the method is successfully performed for each of a pluralityof gaming chips while the gaming chips are stacked.

A method for verifying a payout amount, according to one embodiment,includes determining a value of a gaming chip (including multiple chips)at a table or player position during a game; detecting a change in valueof the gaming chip (again, and in all instances, including multiplechips) at the table or player position; and determining whether thechange in value is valid. Thus, for example, an antenna at a playerstation of a blackjack table (e.g., on the table under the tablecovering, embedded in the table, above or below the table using adirectional antenna, etc.) may determine that chips valued at $1100 arepresent at the player's position at the start of a game, e.g., bydetecting a $1000 chip and a $100 chip. If the player wins, the payoutshould be $1100, which when combined with the original bet will make thetotal value present at the station $2200. If, however, the systemdetects that the value of the gaming chips has jumped to $3100, then itis likely that the dealer has unintentionally or nefariously given theplayer two $1000 chips instead of the one $100 and one $1000 chipmatching the original bet.

A system for performing the method may include a processor and/or otherhardware, optionally in combination with additional logic, forperforming one or more of the operations of the method. The processormay be hardware associated with a reader, and/or may be part of a systemin communication with the reader such as a backend system, server,network-accessible site or device, etc.

The start or end of a game may be detected, and the method performedthereafter. The start or end of the game may be determined, for example,by detecting a signal from a dealer-actuated switch that is pushed priorto or at the start of a game, etc. The start or end of a game may alsobe deduced by logic that infers the start of a game from a change inchip values on the table (e.g., by detecting removal and/or addition ofgaming chips from player positions, detecting removal of payouts, etc.)

In one approach, the start of the game is detected by receiving a signalfrom a sensor coupled to a card shoe. Such a sensor may be a switch thatis actuated as a card is removed from the shoe, an optical sensor thatdetects movement of a card from the shoe, etc. In another approach, thestart of the game is detected by receiving a signal initiated by adealer e.g., as a result of the dealer tripping a switch, stepping on apedal, etc. In yet another approach, the start of the game is detectedby detecting no change in value of the gaming chips at the table for apredetermined amount of time. Typically, no player may change the amountof money played while the initial cards are being dealt. For example, inblackjack, once the first cards come out of the shoe, a player may notchange his or her bet unless some special situation exists, such as theability to double down or split cards.

Preferably, the method is successfully performed for each of a pluralityof gaming chips while the gaming chips are stacked. For example, allgaming chips in a stack may be read while in the stack. Gaming chips areusually maintained and/or transported by players, staff, etc. in stacks.The unique designs of some embodiments of the gaming chips disclosedherein allow reading of a stack of gaming chips.

A method for loyalty tracking according to one embodiment includesdetermining a value of a gaming chip (including multiple chips) at aplayer position (including positions if the player is playing more thanone position) at the start of the game using a radio frequency signal;and recording in a database the value of the gaming chip (includingmultiple chips) at the player position in association with identityinformation of the player. Thus, for example, an antenna at a playerstation of a blackjack table (e.g., on the table under the tablecovering, embedded in the table, etc.) may determine that $1100 ispresent at the player's position at the start of a game, by detecting a$1000 chip and a $100 chip. The recording can be performed on a per-gamebases; the amounts can be accumulated, averaged, etc. over severalgames; statistics calculated and stored; etc. The identity informationmay be or correspond to the player's name, loyalty program identifier(e.g., player card number), etc.

This approach allows, for example, more accurate and consistent trackingof amounts expended by players at a casino. Present methods of loyaltytracking at a gaming table rely on a “pit boss” or other human toperiodically monitor a player to estimate how much a player has played,how long a player has been playing, etc.

A further embodiment includes compiling information such as a value ofchips in a player's possession, identities of other casinos a player hasvisited by identifying the source of the gaming chips in the player'spossession, etc. in combination with determining an identity of theplayer such as by reading a loyalty card of the player that is inproximity to the chips, reading the poker chips at a hotel room doorand/or in a hotel room in which the player is staying, etc.

In addition, advertising and/or offers may be presented to a playerbased on information such as source(s) of the chips in the player'spossession, value of the chips in the player's possession, identity ofthe player, status of the player in a loyalty program, etc.

A system for performing the method may include a processor and/or otherhardware, optionally in combination with additional logic, forperforming one or more of the operations of the method. The processormay be hardware associated with a reader, and/or may be part of a systemin communication with the reader such as a backend system, server,network-accessible site or device, etc.

To allow correlation of the player and the player position, anidentifier of the player may be received. Illustrative examples of howthe identifier of the player can be received include reading of awireless device (e.g., RFID tag, loyalty card, etc.) corresponding tothe player; receiving an identifier obtained from a players card of theplayer, e.g., from a card reader; etc. See also embodiments presentedherein for identifying a player and associating the player with a stackof chips.

In one approach, a change in value of the gaming chip or chips at theplayer position may be detected and the change in value stored in thedatabase. If the player wins, the payout should be $1100, which whencombined with the original bet will make the total value present at thestation $2200. This value can be recorded. Likewise, if the playerloses, no chips will be read at the player position, and the value ofthe chips lost may be recorded. Various approaches may be used toimprove accuracy. For example, to determine whether the player has wonor lost, the value change of the chips at the player position should beequal to the inverse value change in the chip tray (and/or tip box ifpresent). The recording can be performed on a per-game basis; theamounts can be accumulated, averaged, etc. over several games; etc.

Amounts purchased, played, won and/or lost may also be tracked forloyalty program purposes. In one approach, points are assigned to theplayer based on the recorded amounts. For example, when a playerpurchases chips, the dealer may place the player's loyalty card and thechips being purchased at a location on the table where the card andchips are read using RF signals, thereby allowing correlation of thepurchase with the player.

Again, the method is preferably successfully performed for each of aplurality of gaming chips while the gaming chips are stacked. Forexample, all gaming chips in a stack may be read while in the stack.Gaming chips are usually maintained and/or transported by players,staff, etc. in stacks. The unique designs of some embodiments of thegaming chips disclosed herein allow reading of a stack of gaming chips.

A method for loyalty tracking according to one embodiment includesdetermining values of gaming chips (including multiple chips possiblystacked one atop another) played at a player position (includingpositions if the player is playing more than one position) on a gamingtable of any type during games; where a player position may denote an“in play” location where the gaming chips are in play on the table. Suchlocations are usually (but not always) denoted by some type of indicia,box, line, etc. Examples include the pass line on a craps table, arectangle on a blackjack table, a general playing position on a pokertable, etc. A player position in some embodiments may also denote anarea including the “in play” position and a region behind the in playposition (relative to the dealer), where a player usually stacks gamingchips that are not currently in play. The values of the gaming chipsplayed at the player position in association with identity informationof the player are recorded in a database. Thus, for example, an antennaat a player station of a blackjack table (e.g., on the table under thetable covering, embedded in the table, etc.) may determine that $1100 ispresent at the player's position at the start of a game, by detecting a$1000 chip and a $100 chip.

In one approach, changes in values of the gaming chips at the playerposition are detected and the changes in values are stored in thedatabase. If the player wins, the payout should be $1100, which whencombined with the original bet will make the total value present at thestation $2200. This value can be recorded. Likewise, if the playerloses, no chips will be read, and the value of the chips lost may berecorded. Various approaches may be used to improve accuracy. Forexample, to determine whether the player has won or lost, the valuechange of the chips at the player position should be equal to theinverse value change in the chip tray (and/or tip box if present). Therecording can be performed on a per-game basis; the amounts can beaccumulated, averaged, etc. over several games; etc.

Points may be assigned to the player based on the recorded amounts.

Again, the method is preferably successfully performed for each of aplurality of gaming chips while the gaming chips are stacked. Forexample, all gaming chips in a stack may be read while in the stack.Gaming chips are usually maintained and/or transported by players,staff, etc. in stacks. The unique designs of some embodiments of thegaming chips disclosed herein allow reading of a stack of gaming chips.

A system for performing the method may include a processor and/or otherhardware and/or logic for performing one or more of the operations ofthe method. The processor may be hardware associated with a reader,and/or may be part of a system in communication with the reader such asa backend system, server, network-accessible site or device, etc.

In further embodiments, loyalty tracking may be enabled across variousgeographically distinct locations, such as tables or areas in a casino,at remote casinos, restaurants, etc., and the data associated therewithcompiled by a processing system in communication with the various otherlocations. Accordingly, various embodiments described herein may bedeployed at the various locations as part of a larger distributed systemaccording to some embodiments, with data being compiled, e.g., by acentralized system that manages and/or records some aspect of theloyalty program.

A system 400 according to one embodiment is shown in FIG. 4. FIG. 5 is apartial cross sectional view of FIG. 4 taken along Line 5-5 of FIG. 4.As shown, the system includes a gaming table 402 having an RF antenna404 near each player position 406 for wirelessly communicating withgaming chips 408 and/or a wirelessly-readable loyalty card 410 at eachplayer position of a gaming table. A “loyalty card” as referred toherein is meant to denote any device or thing that is known to somesystem to be associated with a particular human, e.g., any itempreassociated with a particular player, and not necessarily having acard form factor or being associated with a loyalty program. The loyaltycard may have an antenna and an RF circuit for enabling wirelesscommunication therewith. Two loyalty cards are shown. The antennas maybe coupled to a reader positioned at the table, remotely therefrom, orto a backend system that acts as a reader.

As shown, the RF antenna 404 is positioned under the table. However, theRF antenna may be embedded in the table as shown in FIGS. 6 and 7.Moreover, the RF antenna need not lie in a plane parallel to thetabletop, but may be oriented at an angle relative thereto, e.g., mayface the player's head, etc. See antenna 404 of FIG. 8.

In addition, an RF antenna 412 may be positioned near a tray 414 of thegaming table for wirelessly communicating with gaming chips in the tray.The antenna 412 may be placed in any appropriate location, includingthat shown, etc. Moreover, multiple antennas may be used. Two antennas412 are shown in FIG. 8.

Directional antennas may be used. Any type of directional antenna knownin the art may be used, including patch antennas. Also preferably, therange of the RF antenna is limited so as to avoid or minimize readingthe chips on an adjacent table, player position, etc. Thus in oneapproach, the RF antenna near the tray of the gaming table isdirectional. In another approach the RF antennas near the playerpositions are directional. In yet another approach, a directionalantenna may be constructed by using shielding to limit the effectivecommunications area of the antenna. For example, a directional ornondirectional antenna may be coupled to a gaming table under a playerposition. An open-topped box of RF shielding material may be positionedaround the sides and bottom of the antenna, thereby limiting sidereading by the antenna.

In one embodiment, an RF antenna 416 may be positioned near a tip box418 of the gaming table for wirelessly communicating with gaming chipsin the tip box. This allows such features as correlating the amount oftips earned with a particular dealer known to be dealing at the table atthe time the chip was read, etc.

Shields may also be employed. For example, a shield may be positionedbetween gaming chips in the tip box and gaming chips in the tray. Forexample all or a portion of the tip box and/or tray may be constructedof a shielding material, where a shielding material is one that blocksat least 95% of RF energy (RF signal) encountering the shieldingmaterial through reflection and/or absorption of the RF energy. Inanother approach, a shielding wall may be present between the playerposition and/or tray and/or tip box.

A shield 420 may be positioned between gaming chips at the playerposition and gaming chips in the tray.

A shield 422 may be positioned between an RF antenna and a player sideof the table for shielding a player from RF energy emitted by the RFantenna. For example, the shield may be a wall that extends downwardlyfrom the table between the tray and the expected player location.

A shield 424 may be positioned between an RF antenna and a dealer sideof the table for shielding a dealer from RF energy emitted by the RFantenna. For example, the shield may be a wall that extends downwardlyfrom the table between the tray and the expected dealer location. Inanother approach, the shield may be arcuate, semi-circular, semi-ovular,circular, ovular, semi-polygonal, polygonal, etc. For example, arectangular shield may be positioned near a tray (e.g., under the table)and have a cross sectional shape that is similar to or slightly largerthan a visible or actual periphery of the tray.

A shield 426 may be located between player positions on the table. SeeFIG. 5. For example, the shield may be formed in the table and/or extendupwardly and/or downwardly therefrom to help isolate adjacent playerpositions so that when the gaming chips at a particular player positionare read, reading of gaming chips at an adjacent player position isavoided or minimized.

In one embodiment, a card reader 428 may be located near each playerposition, as shown in FIG. 4. Thus, a unique card reader may bepositioned near each player position, and/or a card reader may havereading mechanisms near each player position. The card reader mayinclude a slot for accepting a loyalty card (sometimes referred to as aplayers card, reward card, etc.), credit card, etc.

The card reader in another approach may include a directional antenna430 (FIG. 8) for reading a wirelessly-readable card when placed on atable at the player position. The communication mode and/or deviceconfiguration of the wirelessly-readable card may be as set forthelsewhere herein. In another approach, the card reader may include anantenna that reads a player's card via wireless communication while itis on the player's person. In other approaches, the antenna 404 used toread the gaming chips at a player position may perform double duty andread player cards as well.

The card reader in some embodiments may be coupled to or form part of asystem for loyalty tracking. In one approach, a code associated with theplayer to whom the card is issued is received from the card reader,e.g., upon the player inserting the card in the reader. Assuming thereader is associated with a particular player position, the chipspresent at, played, won and/or lost at that position can be correlatedwith the user associated with the card.

In preferred embodiments, the card remains in or near the reader whilethe player associated with the card is playing. This avoids such thingsas associating plays, wins and losses with a player that is no longer atthe table.

In one embodiment, assuming a player wishes to play more than oneposition but has only one loyalty card, an extension card may be placedin or near the card reader of the second position that the player isplaying. The extension card may be issued with the loyalty card, may beprovided to the player by a dealer or pit boss, etc.

An alternate embodiment includes reading a stack of credit cards eachhaving a circuit and a semi-transparent antenna. The credit cards mayeach further comprise a battery.

A method according to another embodiment includes reading RF devicescoupled to photographs in a stack of the photographs, each RF devicehaving a circuit and a semi-transparent antenna coupled thereto.

In any of the embodiments, the gaming chips may be periodicallycommunicated with, e.g., every <1, 1, 5, 10, 30, 60 seconds; may becontinuously and/or consecutively communicated with, e.g., the systemcontinuously monitors the gaming chips at a location, singulating andreading some or all of the chips sequentially, potentially over and overagain in a loop. Standard (known) and/or specialized communicationsprotocols may be used in various embodiments. Illustrative protocolsinclude RFID protocols, WiFi protocols, etc.

Note also that while a large portion of the disclosure refers tosemitransparent gaming chips, it should be kept in mind that the pokerchips may include any type of RF circuit and/or antenna including thosetypes known in the art, including antennas that do not allow asignificant portion of RF energy to pass therethrough. Moreover,alternate antenna designs may be used, such as antennas located on areasof the gaming chips that result in the antennas being misaligned whenviewed in a direction parallel to the stack of chips; antennas thatencircle and/or are positioned along a periphery of the gaming chip;etc.

Moreover, while many embodiments have been described using gaming chips,one skilled in the art will appreciate that some embodiments of thepresent invention may be implemented with other types of items.

For example, one embodiment includes playing cards each having an RFcommunication device, e.g., circuit and antenna. In one approach, the RFdevice or portion thereof (e.g., antenna) is semitransparent asdisclosed herein, thereby allowing reading of a stack of cards. Inanother approach, the antennas in each card are offset so that when thecards are stacked, they may be read. In a further approach, acombination of the two antenna technologies are used.

Methods and/or systems similar to those presented elsewhere herein maybe used to determine validity of each card; determine what a player'sand/or dealer's hand is; determine whether the player has won, lost orpushed based on the dealer's and player's cards; etc.

FIG. 9 illustrates a network architecture 900, in accordance with oneembodiment. As shown in FIG. 9, a plurality of remote networks 902 areprovided including a first remote network 904 and a second remotenetwork 906. A gateway 901 may be coupled between the remote networks902 and a proximate network 908. In the context of the present networkarchitecture 900, the networks 904, 906 may each take any formincluding, but not limited to a LAN, a WAN such as the Internet, PSTN,internal telephone network, etc.

In use, the gateway 901 serves as an entrance point from the remotenetworks 902 to the proximate network 908. As such, the gateway 901 mayfunction as a router, which is capable of directing a given packet ofdata that arrives at the gateway 901, and a switch, which furnishes theactual path in and out of the gateway 901 for a given packet. Furtherincluded is at least one data server 914 coupled to the proximatenetwork 908, and which is accessible from the remote networks 902 viathe gateway 901. It should be noted that the data server(s) 914 mayinclude any type of computing device/groupware. Coupled to each dataserver 914 is a plurality of user devices 916. Such user devices 916 mayinclude a desktop computer, laptop computer, hand-held computer, printeror any other type of logic. It should be noted that a user device 911may also be directly coupled to any of the networks, in one embodiment.

A peripheral 920 or series of peripherals 920, e.g. facsimile machines,printers, networked storage units, etc., may be coupled to one or moreof the networks 904, 906, 908. It should be noted that databases,servers, and/or additional components may be utilized with, orintegrated into, any type of network element coupled to the networks904, 906, 908. In the context of the present description, a networkelement may refer to any component of a network.

The workstation shown in FIG. 10 includes a central processing unit(CPU) 1001 for performing computations, Random Access Memory (RAM) 1002,Read Only Memory (ROM) 1004, an I/O adapter 1006 for connectingperipheral devices such as magnetic storage units 1008, such as a harddisk drive (HDD), to the bus 1012, a user interface adapter 1010 forconnecting a keyboard 1011, a mouse 1013, a speaker 1014, a microphone1015, and/or other user interface devices such as a touch screen, adigital camera (not shown), etc., to the bus 1012, communication adapter1016 for connecting the workstation to a communication network 1018(e.g., a data processing network) and a display adapter 1017 forconnecting the bus 1012 to a display device 1019. The workstation mayhave resident thereon an operating system such as the Microsoft Windows®Operating System (OS), a MAC OS, a UNIX OS, etc. It will be appreciatedthat a preferred embodiment may also be implemented on platforms andoperating systems other than those mentioned. A preferred embodiment maybe written using JAVA, XML, C, and/or C++ language, or other programminglanguages, along with an object oriented programming methodology. Objectoriented programming (OOP), which has become increasingly used todevelop complex applications, may be used.

The description herein is presented to enable any person skilled in theart to make and use the invention and is provided in the context ofparticular applications of the invention and their requirements. Variousmodifications to the disclosed embodiments will be readily apparent tothose skilled in the art and the general principles defined herein maybe applied to other embodiments and applications without departing fromthe spirit and scope of the present invention. Thus, the presentinvention is not intended to be limited to the embodiments shown, but isto be accorded the widest scope consistent with the principles andfeatures disclosed herein.

In particular, various embodiments of the invention discussed herein areimplemented using the Internet as a means of communicating among aplurality of computer systems. One skilled in the art will recognizethat the present invention is not limited to the use of the Internet asa communication medium and that alternative methods of the invention mayaccommodate the use of a private intranet, a Local Area Network (LAN), aWide Area Network (WAN) or other means of communication. In addition,various combinations of wired, wireless (e.g., radio frequency) andoptical communication links may be utilized.

The program environment in which one embodiment of the invention may beexecuted illustratively incorporates one or more general-purposecomputers or special-purpose devices such hand-held computers. Detailsof such devices (e.g., processor, memory, data storage, input and outputdevices) are well known and are omitted for the sake of clarity.

It should also be understood that the techniques of the presentinvention might be implemented using a variety of technologies. Forexample, the methods described herein may be implemented in softwarerunning on a computer system, or implemented in hardware/logic utilizingeither a combination of microprocessors or other specially designedapplication specific integrated circuits, programmable logic devices, orvarious combinations thereof. In particular, methods described hereinmay be implemented by a series of computer-executable instructionsresiding on a storage medium such as a physical computer-readablemedium. In addition, although specific embodiments of the invention mayemploy object-oriented software programming concepts, the invention isnot so limited and is easily adapted to employ other forms of directingthe operation of a computer.

The invention can also be provided in the form of a computer programproduct comprising a computer readable medium having computer codethereon. A computer readable medium can include any physicalnon-transitory medium capable of storing computer code thereon for useby a computer, including optical media such as read only and writeableCD and DVD, magnetic memory such as a hard disk, semiconductor memory(e.g., solid state memory, FLASH memory, portable memory cards, etc.),etc.

Example 1

Gaming chips in a casino each have a passive RF device integratedtherein. The reader, present at a blackjack table for instance, sendsout an interrogation signal sufficient to read all of the chips at thetable (including the players' chips), or at a reduced power to read onlythose chips in the tray. Upon receiving a response from each tag, thereader or a backend system coupled to the reader can quickly determinethe value of the chips on the table and/or in the tray. During activeplay, this information is useful for historical tracking of the flow ofchips in and out of the tray, as well as alerting management to the needto either add chips to the tray or remove chips therefrom. Prior toopening the table or upon closing the table, the chip count in the traycan be quickly and accurately determined by an integrated or portablereader.

Likewise, when a patron wishes to cash out at the cage, the value of astack of chips can be verified by a reader mounted there and comparedagainst the visual chip count.

This feature would also provide a theft deterrent to dealers who may tryto slip chips into their clothing and exit the casino. A reader near theemployee exit can be used to detect chips leaving the casino.

Example 2

Currency in a bank is formed into stacks of 50 bills each. Each bill istagged with a semi-transparent RF device. Several of the stacks areplaced in a bag. Prior to passing the bag to the armored car service,the bag is scanned and the value of the currency is recordedelectronically and potentially sent to a central server accessible via anetwork. A paper report can also be provided to the bank and/or armoredcar service personnel. Upon arrival of the armored car at the FederalReserve depository, the sealed bag is again scanned and the value iscompared to the value it had when it left the bank.

Example 3

Documents, each having a semi-transparent RF device coupled thereto, arestored in a series of rows in a filing room. Someone seeking aparticular document passes a portable reader along each row, pair ofrows, etc. The reader reads each of the tags in the row(s) within rangeof the reader. When the reader finds a match, the reader indicates wherethe document is found, e.g., in row B, section 3.

Example 4

Library books, each having a semi-transparent RF device coupled thereto,are placed in a bin for reshelving. A reader scans the bin and transmitsthe information to the library server. Books indicated as checked out topatrons have their status automatically updated to indicate the booksare available for checkout.

Similarly, during checkout, a patron could set a stack of books on ashelf, where the books are scanned and checked out to the patron.Preferably, the shelf is in a pod or cubicle of shielding material(e.g., metal) that prevents the reader from reading books in adjacentpods.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, and notlimitation. Thus, the breadth and scope of a preferred embodiment shouldnot be limited by any of the above-described exemplary embodiments, butshould be defined only in accordance with the following claims and theirequivalents.

What is claimed is:
 1. A method, comprising: obtaining a first pluralityof identifiers associated with a first plurality of paper currencybills, wherein the first plurality of identifiers are obtained from thefirst plurality of paper currency bills at least in part by wirelesscommunication with the first plurality of paper currency bills;determining whether each of the first plurality of identifiersassociated with the first plurality of paper currency bills is valid,including comparing each of the first plurality of identifiersassociated with the first plurality of paper currency bills to a firstset of valid identifiers; and determining a value of the first pluralityof paper currency bills, utilizing the first plurality of identifiers.2. A method as recited in claim 1, further comprising electronicallyrecording the value of the first plurality of paper currency bills, andsending the recorded value to a central server accessible via a network.3. A method as recited in claim 1, wherein the first plurality of papercurrency bills are arranged in a stacked configuration.
 4. A method asrecited in claim 1, wherein each of the first plurality of papercurrency bills comprises a passive radio frequency identification (RFID)tag.
 5. A method as recited in claim 1, wherein the first plurality ofpaper currency bills are present at a table, and the wirelesscommunication with the first plurality of paper currency bills includesan interrogation signal sent from a directional antenna coupled to alower surface of the table.
 6. A method as recited in claim 1, whereinthe first plurality of identifiers are changeable.
 7. A method asrecited in claim 1, further comprising outputting an alert in responseto determining that one or more of the first plurality of identifiersassociated with the first plurality of paper currency bills is notvalid.
 8. A computer program product, the computer program productcomprising: a non-transitory computer readable medium having computercode stored thereon, the computer code comprising: computer code forobtaining a first plurality of identifiers associated with a firstplurality of paper currency bills, wherein the first plurality ofidentifiers are obtained from the first plurality of paper currencybills at least in part by wireless communication with the firstplurality of paper currency bills; computer code for determining whethereach of the first plurality of identifiers associated with the firstplurality of paper currency bills is valid, including comparing each ofthe first plurality of identifiers associated with the first pluralityof paper currency bills to a first set of valid identifiers; andcomputer code for determining a value of the first plurality of papercurrency bills, utilizing the first plurality of identifiers.
 9. Acomputer program product as recited in claim 8, further comprisingcomputer code for electronically recording the value of the firstplurality of paper currency bills, and sending the recorded value to acentral server accessible via a network.
 10. A computer program productas recited in claim 8, wherein the first plurality of paper currencybills are arranged in a stacked configuration.
 11. A computer programproduct as recited in claim 8, wherein each of the first plurality ofpaper currency bills comprises a passive radio frequency identification(RFID) tag.
 12. A computer program product as recited in claim 8,wherein the first plurality of paper currency bills are present at atable, and the wireless communication with the first plurality of papercurrency bills includes an interrogation signal sent from a directionalantenna coupled to a lower surface of the table.
 13. A computer programproduct as recited in claim 8, wherein the first plurality ofidentifiers are changeable.
 14. A computer program product as recited inclaim 8, further comprising outputting an alert in response todetermining that one or more of the first plurality of identifiersassociated with the first plurality of paper currency bills is notvalid.
 15. A system, including a hardware processor for performing amethod, the method comprising: obtaining a first plurality ofidentifiers associated with a first plurality of paper currency bills,wherein the first plurality of identifiers are obtained from the firstplurality of paper currency bills at least in part by wirelesscommunication with the first plurality of paper currency bills;determining whether each of the first plurality of identifiersassociated with the first plurality of paper currency bills is valid,including comparing each of the first plurality of identifiersassociated with the first plurality of paper currency bills to a firstset of valid identifiers; and determining a value of the first pluralityof paper currency bills, utilizing the first plurality of identifiers.16. A system as recited in claim 15, where the method further compriseselectronically recording the value of the first plurality of papercurrency bills, and sending the recorded value to a central serveraccessible via a network.
 17. A system as recited in claim 15, whereinthe first plurality of paper currency bills are arranged in a stackedconfiguration.
 18. A system as recited in claim 15, wherein each of thefirst plurality of paper currency bills comprises a passive radiofrequency identification (RFID) tag.
 19. A system as recited in claim15, wherein the first plurality of paper currency bills are present at atable, and the wireless communication with the first plurality of papercurrency bills includes an interrogation signal sent from a directionalantenna coupled to a lower surface of the table.
 20. A system as recitedin claim 15, wherein the first plurality of identifiers are changeable.